One type of chair, popular for use as outdoor furniture, is a molded plastic chair. These chairs are a single molded structure and are usually configured so that one chair may be stacked on another chair. Stackable chairs have an advantage in that they can be stacked upon one another and placed on a pallet for easy transport. A retailer may display the stacked chairs on the same pallet on which they have been shipped. Consumers may also store several stackable chairs stacked one upon another.
There are many types of chairs which have cup holders on one or both arms of the chair. One type of cup holder consists of a circular opening in the top surface of the arm of the chair which is sized to receive a cup or other beverage container. The opening may be tapered to hold the cup with a friction fit or there may be a cup-shaped structure below the opening which holds the cup or beverage container. Significant disadvantages of this type of cup holder are that resting one's arm on a chair arm having an opening can be uncomfortable, one's hand may slip and twist into the opening while pushing off from the arm to get up, and any beverage container placed in the opening becomes an impediment to the use of the arm while sitting in or while trying to get out of the chair. Additionally, the opening in the chair arm detracts from the appearance of the chair and objects can fall through or become stuck in the opening.
Another type of cup holder is mounted on and extends outward from the chair arm. Some such cup holders are attached to the arm by straps or clamps and are removable from the chair arm when not in use. Example of this type of cup holder can be found in Published United States Patent Application No. 2006/0061155 A1. This type of holder may be cumbersome to attach and detach. The cup holder may never fit snugly and securely and thus during use the cup holder may slip or fall off from the weight of beverages or from being bumped. If this type of cup holder is stored separately from the chair, the cup holder can easily be misplaced or lost. Of course, this problem can be overcome by permanently attaching the cup holder to the chair arm. But cup holders, especially ones held on by straps or clamps, are not usually aesthetically pleasing and it would be preferable that the cup holder not be visible except when in use. Also, permanently attached cup holders and their connection mechanisms will be prone to collecting dirt and also more difficult to clean. Next, permanently attached cup holders may interfere with people walking by the chair, prevent similar chars from being placed close together side by side, and prevent, or cause uneven, stacking of chairs. Finally, chairs with permanent holders take up more space in storage and, if attached at the factory, permanent cup holders would likely dramatically reduce the number of chairs that would fit on a tractor trailer, thereby increasing shipping costs.
Yet, another type of cup holder is attached to the underside of a chair arm or to the arm support and can pivot or rotate between a closed position in which the cup holder is nested under the arm of the chair for storage and an extended position for use. U.S. Pat. Nos. 6,361,105 B1 and 8,182,031 B2 disclose this type of cup holder. While this type of cup holder does not have many of the problems of the other cup holders described above, there are still serious issues that include:                1) A lack of structure whereby the cup holder itself is not sufficiently robust. This type of cup holder is essentially a cantilever beam with a fixed end and a floating or free end. As such, loads or forces that are applied to the cup holder are magnified towards the fixed end. This is because the moment increases towards the fixed end of a cantilever beam. So, when beverages are placed in the cup holder, it may sag unacceptably due to a lack of structure especially near the fixed end where the forces are greater. Also, cup holders that swing out to the side of the arm are put into a highly exposed position where at times they may get sat on or pushed down on or otherwise experience some manner of excessive loading or abuse. For any given chair, it may not happen frequently or may never happen, but some form of accidental excessing loading may happen one or more times to a significant number of chairs. This type of cup holder may crack if it is subjected to just one occurrence of excessive loading.        2) Bolts or screws that are feasible for use in attaching the cup holder will likely not provide adequate purchase because their diameter is simply not large enough to create sufficient grip between the threads and the plastic pilot hole. Moving to a bolt or screw with a large enough diameter to achieve sufficient purchase may be cost prohibitive or create other problems such as large diameter bolts or screws might distort the boss they are being driven into such that the whole system would bind up and the cup holder would not be able to rotate. Bolts or screws of a diameter feasible to use may tear out during normal usage or instances of inadvertent higher-than-normal pressures on the cup holder, such as if someone accidentally pushed down on the cup holder when getting out of the chair. If the bolt or screw were torn out, even just once, this would likely strip the pilot hole into which the bolt or screw was driven. Once the pilot hole for the boss or screw has been stripped out, there would either be no way to reaffix the cup holder to the chair, or, if it could be reaffixed, the gripping strength of the bolt or screw may be so compromised that the cup holder may no longer be able to function without frequently coming loose and falling off of the chair. It is worth noting that with this type of cup holder, torque is created when the cup holder is loaded and this torque acts directly on the bolt or screw. As a result any loading on the cup holder will be concentrated on the portion of the threads facing towards the loading. This concentration of loading exacerbates the deficiency of bolts or screws as a way to attach this type of cup holder.        3) Cup holders of this type do not have a break-away mechanism. We have discussed how, during excessive loading, it is possible that the cup holder could fail, or that the bolt/screw connecting the cup holder to the chair could fail. A third possibility is that the chair or chair arm would fail. Severe cracking may occur, severe enough where the chair damage would be very conspicuous. In which case the chair should and would often be discarded. This means the whole chair would be lost due to an issue with just the cup holder. Or there could be less severe cracking, whereby the damage either went unnoticed or was deemed not severe enough to scrap the chair over. In either event, the chair might remain in service and the chair or chair arm might fail during continued use and potentially injure someone.        4) When desiring the cup holder to stay in the retracted position, it may not oblige, swinging either partially or fully open. This could simply look sloppy, or, if trying to move the chair around, cause the cup holder to bang into doorframes or catch on other objects.        5) When desiring the cup holder to stay in the open position, if the chair were on a slightly uneven surface, it may try to swing partially or fully closed. A cup holder that does not remain stationary in the open position may cause beverages to be in different positions relative to the chair arm or block the cup holder opening and thus prevent one from putting a beverage in the holder. The cup holder may also rotate slightly when a beverage is put into or taken out of the holder, when it would be preferable if the cup holder would just stay in one place.        6) It might be difficult to open the cup holder as one may have to bend their head over the side of the chair to see where the cup holder is, and even then, one might not know which end of the cup holder to pull out on.        7) When opening the cup holder, one might damage the cup holder if they pull it open too hard as there is no defined stopping point for the cup holder and it could be rotated beyond its intended open position to a point where components are stretched, cracked, or otherwise stressed and damaged. The same might occur if the cup holder were closed forcefully where it would be rotated beyond the closed position and damaged.        8) A screw gun or some other power tool would likely be necessary to perform the assembly of this type of cup holder in a timely manner. Power tools are expensive and can break. Plus assemblers may have difficulty using them or achieving just the right amount of torque on the bolt or screw to achieve a proper tightness. If the bolt or screw is too loose the cup holder may wobble, if too tight the cup holder may not rotate easily.        9) This type of cup holder may also prevent or impede stacking of the chair, as the cumulative height of the chair arm and the cup holder could be significant.        
In summary, cup holders such as disclosed in U.S. Pat. Nos. 6,361,105 B1 and 8,182,031 B2 have a variety of weaknesses.
There is a need for a molded plastic chair having a cup holder which can be stacked one upon another for storage and shipment. Preferably the cup holder is retractable and will stay in either the storage position or the extended position after being placed in that position by the user. Preferably it will have sufficient structure to be able to withstand normal usage. Preferably there will be a robust connection between the cup holder and chair. Preferably there will be a break-away mechanism, such that if the cup holder were knocked off by accident, no components in the system (i.e. neither the chair arm, the connector holding the cup holder to the arm, nor the cup holder itself) would be damaged and preferably the cup holder could be reinstalled multiple times with no loss in functionality. Preferably the cup holder will have a no-look gripping tab; one that can be located by touch without having to look over the side of the chair arm. Preferably the cup holder will feature definite, sturdy stops for when it has reached either its fully opened or fully closed positions. Rough-handling users should not be able to damage the cup holder by swiveling it beyond its fully-open or fully-closed position, and the cup holder should, once closed, be aligned on its outer edge in parallel with the outside of the chair arm. Preferably the cup holder could be assembled quickly and easily either by hand or with a small mallet. The cup holder should be capable of holding cups, cans, mugs, tumblers, wine glasses and all commonly used types of beverage bottles from which people routinely drink. Preferably the cup holder is made of that same or similar plastic as the chair to which it is attached.